CNC

44 views
Skip to first unread message

Eric J. Kaplan

unread,
Apr 11, 2014, 4:13:34 PM4/11/14
to omaha-ma...@googlegroups.com
Still working on some details, but chances are high that we will be given a new Shapeoko CNC Mill, courtesy of Inventables, in the coming weeks!

This will be an awesome addition to our ever-growing arsenal of tools, and should pair nicely with our 3D printer and laser cutter.

More details to come!

Sent from Eric's iPhone

David Knaack

unread,
Apr 11, 2014, 4:37:14 PM4/11/14
to OMG
They have a quick overview of a tool chain that works with it here:




--
Support Omaha Maker Group with purchases you make anyway. Shop Amazon using our Affiliates link, and OMG receives a portion of the proceeds. http://amzn.to/1f3i3ve


Leave lurking behind -- come visit us at the Makery at 8410 K Street, #5, Omaha (just off 84th & L). We're nice, we promise. http://bit.ly/1dKnTmC
---
You received this message because you are subscribed to the Google Groups "Omaha Maker Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email to omaha-maker-gr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

Brandon Norris

unread,
Apr 11, 2014, 4:51:22 PM4/11/14
to omaha-ma...@googlegroups.com
I believe we are getting early access to their new tool chain, http://www.easel.com/ which looks like it will be pretty decent.


Leave lurking behind — come visit us at the Makery at 8410 K Street, #5, Omaha (just off 84th & L). We’re nice, we promise. http://bit.ly/1dKnTmC

Dan Linder

unread,
Apr 12, 2014, 6:58:32 AM4/12/14
to omaha-ma...@googlegroups.com
Congrats and thanks to those involved who made this possible!

Dan
--
***************** ************* *********** ******* ***** *** **
"Quis custodiet ipsos custodes?"
    (Who can watch the watchmen?)
    -- from the Satires of Juvenal
"I do not fear computers, I fear the lack of them."
    -- Isaac Asimov (Author)
** *** ***** ******* *********** ************* *****************

Jason Webb

unread,
Apr 13, 2014, 9:00:25 PM4/13/14
to omaha-ma...@googlegroups.com
Awesome news! Will they send an original ShapeOko, or a ShapeOko 2?

I have an original Shapeoko that I bought over a year ago, but never used it. I found out too late that there are no good, free way to use it to carve 3D models out of material :( All of the focus seems to be on routing, rather than milling, i.e. cutting flat 2D designs out of stock. Makercam and Easel are popular, but only do 2D stuff.

If you already have a laser cutter and a 3D printer, it's hard to find a use for a CNC mill that you can only do on the mill. You may be able to cut aluminum stock, but that (used to) require upgrades.

Someday I'm hoping to get the funds to purchase CamBam, which you can use to generate GCode from STL models. I'd be super interested in seeing if anyone finds a good way to carve 3D models with the machine though!

Ben Hutcheson

unread,
Apr 13, 2014, 10:57:25 PM4/13/14
to omaha-ma...@googlegroups.com
As the original Shapeoko is no longer available, I would assume we are getting the Shapeoko2 kit, but it has not been specified.

Software has always been the big issue with milling machines.  We've had a fairly capable CNC mill at the Makery for several years, but it has seen almost no use largely because there's no clearly defined toolchain.  However, one of Inventables's stated goals with this donation is to teach more people to use these machines and hopefully start to approach the level of adoption seen by 3D printers.  I am not familiar with Easel and don't know what it can currently do or what their long-term plans for it are.  No promises about 3D, at least in the short term.

Still, even if we find the machine is more usable for 2D work than 3D work, it would still be useful alongside the laser cutter.  The laser can generally cut birch plywood and acrylic up to 1/8" thick.  Experiments with thicker materials, hardwoods, polycarbonate, various foams, coroplast, food items, and of course metals have been unsuccessful, and some plastics like PVC are completely forbidden.  So even if the mill is intended mostly for 2D work, it opens up a lot of possibilities beyond the laser.  1/4" plywood is much cheaper and stronger than 1/8" plywood.  We've got a ton of Sintra (expanded PVC board) at the Makery, and we can't cut it on the laser.  And cutting accurate, complex shapes out of something more attractive than plywood is also compelling; I'd love to make a solid Walnut robot arm.  Plus, the cut area of the Shapeoko2 is larger than that of our laser, and can be expanded easily.


--
Support Omaha Maker Group with purchases you make anyway. Shop Amazon using our Affiliates link, and OMG receives a portion of the proceeds. http://amzn.to/1f3i3ve
 
 

David Knaack

unread,
Apr 13, 2014, 11:55:37 PM4/13/14
to OMG
Which packages did you try? I've heard good things about PyCAM, but haven't tried it myself.


On Sun, Apr 13, 2014 at 8:00 PM, Jason Webb <zen....@gmail.com> wrote:

--
Support Omaha Maker Group with purchases you make anyway. Shop Amazon using our Affiliates link, and OMG receives a portion of the proceeds. http://amzn.to/1f3i3ve
 
 

Jason Webb

unread,
Apr 14, 2014, 5:42:07 PM4/14/14
to omaha-ma...@googlegroups.com
Very good points about uses for the machine. Since I don't use laser cutters very much, I keep forgetting that hobby-level cutters can't cut through much, so a mill/router would definitely be great for most materials you could grab at a hardware store.

I've tried PyCAM, OpenSCAM, HeeksCNC and FreeMill, but found them all to be really hard to understand and use. Since I've never done CNC milling/routing before (and don't know anyone who has as a hobbyist) I have no clue what I'm doing, haha. With 3D printing the workflow is relatively simple and there is a ton of good documentation about the process online. But with CNC work there is very little information, and most of it is (in my opinion) overly technical. 

I think the Shapeoko really needs a ReplicatorG. You select a couple of basic parameters (what bit you're using, what material you want to cut) and open an STL file, then slice it up and go. But right now it's a pretty big time investment to figure it all out for newbies like me. Looking forward to sharing experiences with you guys as you learn.

William Holcombe

unread,
Apr 14, 2014, 10:56:21 PM4/14/14
to omaha-ma...@googlegroups.com
Awesome news! I completely agree, cam programs are not very user-friendly. Ive asked several of my machining teachers why im using software that feels like it was made in the 90's and not changed since and I haven't got a straight answer yet ;P

Things like work holding and spindle movement are more technical with a mill than a 3d printer or plasma cutter when you account for vibration, speeds and feeds (in school we ignore the suggested ones for materials half the time and just do what our teacher says or change it during cutting because "it doesn't sound/look right") and differences in cutters due to initial quality and wear. Perhaps more varying technical information demands more user input? 

The ReplicatorG would be the way to go, (why haven't they thought of that!) much more intuitive.

Looking forward to the new one! Maybe they have worked some things out to make it easier?


--

Jason Webb

unread,
Apr 15, 2014, 3:29:21 PM4/15/14
to omaha-ma...@googlegroups.com
Theoretically, using a CNC mill doesn't *need* to be more difficult than using a 3D printer. Things like work holding, spindle speed, bit type/size are really very similar to things all 3D printing enthusiasts must learn anyway - using a heated bed/Kapton/hairspray/etc to hold pieces to build platform, feed and movement rates of the head, nozzle diameter, and so on. The main difference in operation (I think) is that the 'nozzle' of the mill is swapped out much more often, even several times during a job. But this is not drastically different than what a 3D printer user might do if they were using the printer seriously.

Believe it or not, the slicing engine that RepG uses (Skeinforge) supposedly is able to generate Gcode for carving, rather than additive manufacturing. It also has one of the worst interfaces known to mankind, lol. I think I've only see one or two people ever use it that way, and they went through a heck of a lot of work.

Milling definitely requires more work than 3D printing, but not dramatically more. I really think if the Shapeoko team started with the work being done in the 3D printing world and tweaked it, they could create a branch of RepG, Slic3r or Cura that has has extra features for milling. 

Check out what the folks at Othermill have cooked up for their mill. It's Mac only, but it's definitely the kind of thing I'd want to use: http://othermachine.co/products/otherplan/

Anyway, regardless of software, the Shapeoko machine (especially 2) is phenomenal, and will open up tons of possibilities for cool work for everyone. I'm really amazed that Inventables is giving one away - they are awesome!

David Knaack

unread,
Apr 15, 2014, 3:58:59 PM4/15/14
to OMG
I think sometimes people get too hung up on trying to get perfect 3D contouring out of their mill. It isn't hard to get results similar to a 3D printer, though there are more constraints.

When I was working with mine I found that I didn't actually have all that much need for actual 3D parts, 2.5D was fine for most parts. 


--

Jason Webb

unread,
Apr 15, 2014, 5:24:17 PM4/15/14
to omaha-ma...@googlegroups.com
Having access to someone like you who knows a thing or two about machining would be a huge advantage for learning about the processes and workflows. I'll be moving to Omaha in about a month, and I look forward to learning from you in the future :P

I bought my mill solely for creative purposes - I'm pretty much completely interested in making fluid, 3D forms based on generative designs in more attractive materials than ABS/PLA can provide. So, pretty much the least easy for hobbyists, apparently :P

This is the type of work I am almost purely interested in doing with my mill (lol): https://twitter.com/brianringley/status/439854676633477120. Using nice woods, wax and foam to produce models. Maybe even making more precise parts for investment casting. Someday I'll figure it out!

Maybe I don't have a complete understanding of 2.5D vs. 3D too. Would the foam piece in that Twitter post be 2.5D or 3D?

David Knaack

unread,
Apr 15, 2014, 5:47:42 PM4/15/14
to OMG
That foam piece is definitely a 3D process. 2.5D is your traditional flat drawing stuff, you have a bunch of lines in flat layers, and then in CAM you can define how each layer should be cut. A dumb CAM processor might just turn the lines directly into toolpaths. A smarter processor might let you define things like what sort of pocket to cut, how deep the tool can cut per pass, and cutter diameter.

3D stuff like that foam model can be cut with a variety of strategies too. Usually roughing is done with a basic endmill, and then you go back to do one or more finish passes with a ball. Software that is smart about how it traces contours can save a lot of time by doing some semi-advanced finishing like waterline tracing, or advanced techniques where it recognizes and traces fillets, or performs undercuts and such things.

When you aren't charging someone per-job, time isn't usually an overriding concern, and in foam or wax you can usually run the machine balls-out, so doing simple cut strategies like XY rastering is fine. No need for fancy CAM software in that case, just rough with a good-sized endmill and use a finishing pass with a tiny stepover and the smallest diameter ball mill that will fit in the surface features of your model and you should get a good result.


--

Jason Webb

unread,
Apr 15, 2014, 6:04:59 PM4/15/14
to omaha-ma...@googlegroups.com
When the machine arrives, you ought to give a presentation / workshop about the terminology used in CNC machining and the general software workflow! As I said, I'm considering investing in CamBam someday, but if you can help the OMG people (and me) how to use something like PyCAM to do 3D milling in foam, you have no idea how happy that would make me! 

Out of curiosity, what CAM package do you like the most? If you had to choose a free package, which seems the best to you?

David Knaack

unread,
Apr 15, 2014, 7:06:19 PM4/15/14
to OMG
I certainly can't claim to be an expert, but I'd be happy to give an overview of the process, unless someone else gets to it first. I'm not sure how much of what I know is applicable to their toolchain.

The toolchain I was using is several years old now, so probably not really useful, but here goes. 

For 2.5D I usually used a CAD program to do a DXF drawing which I would bring into either ACE Converter (free open source program that converts DXF directly into tool paths), or SheetCAM (commercial, supports a variety of milling, pocketing and tracing operations). 

For 3D I'd use Blender to model the part, then I'd import it into MeshCAM (commercial) or some free package with few features that I can't remember the name of to generate gcode.

I'd save the gcode to the network, then on the machine I'd fire up the Win98 GUI to use the network to copy the file over (batch file in startup, just copied everything from a fixed location on the network, then dropped back to DOS mode). Back in DOS I open TurboCNC (shareware, source with registration) and set up to run the code.

A similar modern chain would probably be about the same, just using something like Universal-G-Code-Sender to send gcode to an Arduino-based machine controller instead of mucking about with DOS. You could also use LinuxCNC (that's what the CNC mill at the Makery is running).

You could also use a suite CAD/CAM package like MecSoft's tools (there are a number of these out there, and they are all expensive), but generally the output is going to be a gcode file that you feed to your machine via whatever interface it supports.

It would be pretty cool for a small machine to use an integrated CAM/CNC controller package similar to the 3D printing software, so you go get a model somewhere and just have the one package to consume the model and run the machine. Like you were saying earlier, that would make the process much more accessible.


On Tue, Apr 15, 2014 at 5:04 PM, Jason Webb <zen....@gmail.com> wrote:
When the machine arrives, you ought to give a presentation / workshop about the terminology used in CNC machining and the general software workflow! As I said, I'm considering investing in CamBam someday, but if you can help the OMG people (and me) how to use something like PyCAM to do 3D milling in foam, you have no idea how happy that would make me! 

Out of curiosity, what CAM package do you like the most? If you had to choose a free package, which seems the best to you?

--
Reply all
Reply to author
Forward
0 new messages